Part of our offseason work on the diamonds is to rate each and every offensive player we expect to get playing time. We’ve had plenty of time to do that this season, with the major sports markets in a standstill. The good news is even if this season doesn’t play out these numbers will prepare us for next year.
The best one number in our opinion to do this is wRC, a runs created tool. The league average player rates out to be 100. Any number higher is that much better than league average, and any number lower is worse than league average. We take it one step further and break each player down vs lefty and righty pitchers. We also use the last three years to increase sample size. By doing this we can then add up each starting player in order to get an offensive team total number for both squads.
While most star players are obviously better than average regardless of the handedness of the pitcher, certain players have major differences. For example Arizona is the new home of Starling Marte. The last three seasons he is just 76 vs lefties, 24% worse than league average. But 121, 21% higher than league average vs righties. He is projected to have 609 plate appearances. So being virtually an everyday player, we can look to find value going against the Diamondbacks when facing left-handed pitchers.
Something else we want to look at is roster flexibility. Since Marte is a center fielder, we want to see how other players do vs lefties that can also play the position. Not many teams have more than one player that excels in center. The D’Backs have five players on the projected roster that can play this position. In addition to Starling Marte they have T Locastro, K Marte, D Peralta and J Jay. Versus lefties we see wRC+ numbers of 93 for Locastro, 143 for Marte, 85 for Peralta and 85 for Jay. So by far the best hitter vs lefties in Ketel Marte. But he’s expected to get 84% of his playing time at second base. So that same procedure has to be done at that position, and so on.
It turns out only E Escobar is better than league average at second base, but he looks to play 85% of his games at third base. And the backups at third are weak against lefties. As a whole Arizona has six players better than league average vs southpaws, and eight players better than average vs righties.
Do this for the entire league and you can find value on a daily basis.